You don’t need a fortune to start an ecommerce business. Without a physical store, maintenance expenses and (usually) labor expenses are significantly reduced for online sellers. With these low startup costs, many merchants flock to sell online with the hope of making an easy profit.

However, running a profitable ecommerce business isn’t a matter of luck — it’s a calculated effort that requires constant observation and iteration. You need to track the demand of your products to estimate how much you can sell and earn on your orders. You also have to regularly calculate your net profit margin to assess what steps you need to take, such as cutting costs or increasing sales, to maintain profitability...